56fb5fe9f1
This changes all HWRNG driver initcalls to module_init(). We must probe the RNGs after the major kernel subsystems are already up and running (like PCI). This fixes Bug 7730. http://bugzilla.kernel.org/show_bug.cgi?id=7730 Signed-off-by: Michael Buesch <mb@bu3sch.de> Cc: Jan Beulich <jbeulich@novell.com> Cc: Jeff Garzik <jeff@garzik.org> Cc: Greg KH <greg@kroah.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@osdl.org>
152 lines
3.3 KiB
C
152 lines
3.3 KiB
C
/*
|
|
* RNG driver for AMD RNGs
|
|
*
|
|
* Copyright 2005 (c) MontaVista Software, Inc.
|
|
*
|
|
* with the majority of the code coming from:
|
|
*
|
|
* Hardware driver for the Intel/AMD/VIA Random Number Generators (RNG)
|
|
* (c) Copyright 2003 Red Hat Inc <jgarzik@redhat.com>
|
|
*
|
|
* derived from
|
|
*
|
|
* Hardware driver for the AMD 768 Random Number Generator (RNG)
|
|
* (c) Copyright 2001 Red Hat Inc <alan@redhat.com>
|
|
*
|
|
* derived from
|
|
*
|
|
* Hardware driver for Intel i810 Random Number Generator (RNG)
|
|
* Copyright 2000,2001 Jeff Garzik <jgarzik@pobox.com>
|
|
* Copyright 2000,2001 Philipp Rumpf <prumpf@mandrakesoft.com>
|
|
*
|
|
* This file is licensed under the terms of the GNU General Public
|
|
* License version 2. This program is licensed "as is" without any
|
|
* warranty of any kind, whether express or implied.
|
|
*/
|
|
|
|
#include <linux/module.h>
|
|
#include <linux/kernel.h>
|
|
#include <linux/pci.h>
|
|
#include <linux/hw_random.h>
|
|
#include <asm/io.h>
|
|
|
|
|
|
#define PFX KBUILD_MODNAME ": "
|
|
|
|
|
|
/*
|
|
* Data for PCI driver interface
|
|
*
|
|
* This data only exists for exporting the supported
|
|
* PCI ids via MODULE_DEVICE_TABLE. We do not actually
|
|
* register a pci_driver, because someone else might one day
|
|
* want to register another driver on the same PCI id.
|
|
*/
|
|
static const struct pci_device_id pci_tbl[] = {
|
|
{ 0x1022, 0x7443, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
|
|
{ 0x1022, 0x746b, PCI_ANY_ID, PCI_ANY_ID, 0, 0, 0, },
|
|
{ 0, }, /* terminate list */
|
|
};
|
|
MODULE_DEVICE_TABLE(pci, pci_tbl);
|
|
|
|
static struct pci_dev *amd_pdev;
|
|
|
|
|
|
static int amd_rng_data_present(struct hwrng *rng)
|
|
{
|
|
u32 pmbase = (u32)rng->priv;
|
|
|
|
return !!(inl(pmbase + 0xF4) & 1);
|
|
}
|
|
|
|
static int amd_rng_data_read(struct hwrng *rng, u32 *data)
|
|
{
|
|
u32 pmbase = (u32)rng->priv;
|
|
|
|
*data = inl(pmbase + 0xF0);
|
|
|
|
return 4;
|
|
}
|
|
|
|
static int amd_rng_init(struct hwrng *rng)
|
|
{
|
|
u8 rnen;
|
|
|
|
pci_read_config_byte(amd_pdev, 0x40, &rnen);
|
|
rnen |= (1 << 7); /* RNG on */
|
|
pci_write_config_byte(amd_pdev, 0x40, rnen);
|
|
|
|
pci_read_config_byte(amd_pdev, 0x41, &rnen);
|
|
rnen |= (1 << 7); /* PMIO enable */
|
|
pci_write_config_byte(amd_pdev, 0x41, rnen);
|
|
|
|
return 0;
|
|
}
|
|
|
|
static void amd_rng_cleanup(struct hwrng *rng)
|
|
{
|
|
u8 rnen;
|
|
|
|
pci_read_config_byte(amd_pdev, 0x40, &rnen);
|
|
rnen &= ~(1 << 7); /* RNG off */
|
|
pci_write_config_byte(amd_pdev, 0x40, rnen);
|
|
}
|
|
|
|
|
|
static struct hwrng amd_rng = {
|
|
.name = "amd",
|
|
.init = amd_rng_init,
|
|
.cleanup = amd_rng_cleanup,
|
|
.data_present = amd_rng_data_present,
|
|
.data_read = amd_rng_data_read,
|
|
};
|
|
|
|
|
|
static int __init mod_init(void)
|
|
{
|
|
int err = -ENODEV;
|
|
struct pci_dev *pdev = NULL;
|
|
const struct pci_device_id *ent;
|
|
u32 pmbase;
|
|
|
|
for_each_pci_dev(pdev) {
|
|
ent = pci_match_id(pci_tbl, pdev);
|
|
if (ent)
|
|
goto found;
|
|
}
|
|
/* Device not found. */
|
|
goto out;
|
|
|
|
found:
|
|
err = pci_read_config_dword(pdev, 0x58, &pmbase);
|
|
if (err)
|
|
goto out;
|
|
err = -EIO;
|
|
pmbase &= 0x0000FF00;
|
|
if (pmbase == 0)
|
|
goto out;
|
|
amd_rng.priv = (unsigned long)pmbase;
|
|
amd_pdev = pdev;
|
|
|
|
printk(KERN_INFO "AMD768 RNG detected\n");
|
|
err = hwrng_register(&amd_rng);
|
|
if (err) {
|
|
printk(KERN_ERR PFX "RNG registering failed (%d)\n",
|
|
err);
|
|
goto out;
|
|
}
|
|
out:
|
|
return err;
|
|
}
|
|
|
|
static void __exit mod_exit(void)
|
|
{
|
|
hwrng_unregister(&amd_rng);
|
|
}
|
|
|
|
module_init(mod_init);
|
|
module_exit(mod_exit);
|
|
|
|
MODULE_AUTHOR("The Linux Kernel team");
|
|
MODULE_DESCRIPTION("H/W RNG driver for AMD chipsets");
|
|
MODULE_LICENSE("GPL");
|